Does your child text? Does he or she drive? Chances are they’re doing both at the same time. According to the Insurance Institute of Highway Safety, 40 percent of drivers reported they're on theircellphones while driving at least a few times per week, and 19 percent talk daily. As a result, 22 percent of car accidents in 2009 were caused by cellphone usage.

Since adults can’t seem to stop themselves from deadly in-car multitasking, it’s probably not realistic to expect your teen to refrain from using his or her phone while driving.

Fortunately there are solutions that automatically kick in when the car starts rolling. These solutions come in two basic types:

Cellphone applications
Apps such as T-Mobile's DriveSmart Plus and Key2SafeDriving sense when you’re driving, usually by GPS measuring your speed, and disable most or all of your phone's functionality once a pre-determined speed is reached.

All offer some sort of emergency override and passenger-usage exceptions, and some include Web-based cell-phone-use monitoring. You can opt into receiving messages whenever the app is overridden for cell phone use while driving.

Combination hardware/apps
These solutions work like the stand-alone apps, except instead of relying on GPS to sense car usage, a small module gets attached to a part of your car such as the emergency brake or the OBD (on-board diagnostics) module.

Once the module is triggered by car usage, a signal disables your phone. Another set of solutions uses a Bluetooth module to enable all-voice and text-to-speech capabilities.